Came across this note after a trip to Worcestershire to look at some offerings. Checked PMG and it's top of the population report and only 1 graded. No idea of value.
Wow man!! What does the other side look like? If that is a 58, then I would like to see Uncirculated specimens. It's very nice looking for a foreign note. I'm a U.S collector mostly. Enjoy your weekend.
Not really: most printer's proofs come as uniface (1 sided printing) that I know of. Maybe you are thinking of colour trial? Colour trials usually have both sides printed, I believe. Anyway, you won't see serial numbers nor signatures either. This is very niche area of collecting as even collecting specimens is more common (& it's niche). I don't think it's that unusual to have a pop report of 1 for a proof. They were mainly used by printers & never meant for circulation- they should be pretty uncommon. Value? Whatever you paid for it, I guess. That's what editors of catalogues do- they research what collectors are willing to pay & submit these averaged out prices.
Probably 1923 unless a competitor was trying to get more business and issued a later printers proof. Hard to prove.